package org.iteam.core.lucene;
/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.IOException;
import java.io.Reader;

/**
 * CharReader is a Reader wrapper. It reads chars from Reader and outputs
 * {@link CharStream}, defining an identify function {@link #correctOffset}
 * method that simply returns the provided offset.
 */
public final class CharReader extends CharStream {

	private final Reader input;

	@SuppressWarnings("resource")
	public static CharStream get(Reader input) {
		return input instanceof CharStream ? (CharStream) input
				: new CharReader(input);
	}

	private CharReader(Reader in) {
		input = in;
	}

	@Override
	public int correctOffset(int currentOff) {
		return currentOff;
	}

	@Override
	public void close() throws IOException {
		input.close();
	}

	@Override
	public int read(char[] cbuf, int off, int len) throws IOException {
		return input.read(cbuf, off, len);
	}

	@Override
	public boolean markSupported() {
		return input.markSupported();
	}

	@Override
	public void mark(int readAheadLimit) throws IOException {
		input.mark(readAheadLimit);
	}

	@Override
	public void reset() throws IOException {
		input.reset();
	}
}
